1. Field of the Invention
The present invention relates to a method of determining the position of a particular frame on a film by detection of blip marks provided for respective frames on the film in advance. The present invention also pertains to an apparatus which may suitably be employed for carrying out said method.
2. Description of the Related Art
In the conventional frame position determining system of the type described above, it is necessary, in order to increase the degree of accuracy in suspending the feed of a film, to determine a blip mark immediately when detecting a rise of a pulse of a blip mark detecting signal, and this involves the problem that dust which is attached to the surface of a film is misjudged to be a blip mark. To overcome such disadvantage, a system has already been devised in which a blip mark is discriminated from dust by detecting blip mark at two positions.
In U.S. Pat. Nos. 3,802,771 and 3,629,840, for example, such a system has been proposed that the blip mark is detected by arrangement of a plurality of blip mark detectors.
The above-described conventional system, however, needs to provide blip mark detectors at two positions, respectively, which means that the number of input and output devices is increased and the arrangement of the apparatus is complicated, disadvantageously.
Also, an image data processing system to which the present invention is suitably applied has been proposed in U.S. application Ser. No. 884,344.